STM32WBA: zephyr/drivers/flash/flash_stm32wba_fm.c: flash_stm32_erase: unexpected erase size #84842
Description
Describe the bug
During firmware update with MCUboot/ MCUmgr I’m facing the issue that the first flash page of my storage partition, which is located direct after the image-1 partition, is erased.
After some research I found out, that this happens during the erase of the image trailer area of image-1 slot, which is located at the end of the image-1 partition. At this point there should be one flash page (8192 byte) erased, but actually there were two pages erased (the last page of image-1 partition and the first page of the storage partition).
It seams that the flash_stm32_erase() function of zephyr/drivers/flash/flash_stm32wba_fm.c handles the case when len is equal FLASH_PAGE_SIZE not correct.
In this case sect_num becomes 2 instead of 1, which leads in two erased pages instead of one.
To Reproduce
Create a basic Zephyr application with main.c and prj.conf as shown below:
main.c
#include <zephyr/kernel.h>
#include <zephyr/logging/log.h>
#include "zephyr/device.h"
#include <zephyr/drivers/flash.h>
LOG_MODULE_REGISTER(main);
#define FLASH_SECTOR_SIZE 0x2000
#define OFFSET_SECTOR_1 0xFA000
#define OFFSET_SECTOR_2 0xFC000
#define SECTOR_1 (OFFSET_SECTOR_1 / FLASH_SECTOR_SIZE)
#define SECTOR_2 (OFFSET_SECTOR_2 / FLASH_SECTOR_SIZE)
int main(void)
{
const struct device *flash = DEVICE_DT_GET(DT_CHOSEN(zephyr_flash_controller));
if (!device_is_ready(flash)) {
printk("%s: device not ready.\n", flash->name);
return 0;
}
uint32_t writeBuffer[] = {0xAAAAAAAA, 0xBBBBBBBB, 0xCCCCCCCC, 0xDDDDDDDD};
flash_write(flash, OFFSET_SECTOR_1, &writeBuffer, sizeof(writeBuffer));
flash_write(flash, OFFSET_SECTOR_2, &writeBuffer, sizeof(writeBuffer));
LOG_INF("Write buffer to sector %d: 0x%08x 0x%08x 0x%08x 0x%08x", SECTOR_1, writeBuffer[0],
writeBuffer[1], writeBuffer[2], writeBuffer[3]);
LOG_INF("Write buffer to sector %d: 0x%08x 0x%08x 0x%08x 0x%08x", SECTOR_2, writeBuffer[0],
writeBuffer[1], writeBuffer[2], writeBuffer[3]);
flash_erase(flash, OFFSET_SECTOR_1, FLASH_SECTOR_SIZE);
LOG_INF("Erased sector %d", SECTOR_1);
uint32_t readBufferSector1[4];
uint32_t readBufferSector2[4];
flash_read(flash, OFFSET_SECTOR_1, readBufferSector1, sizeof(readBufferSector1));
flash_read(flash, OFFSET_SECTOR_2, readBufferSector2, sizeof(readBufferSector2));
LOG_INF("Read buffer from sector %d: 0x%08x 0x%08x 0x%08x 0x%08x", SECTOR_1,
readBufferSector1[0], readBufferSector1[1], readBufferSector1[2],
readBufferSector1[3]);
LOG_INF("Read buffer from sector %d: 0x%08x 0x%08x 0x%08x 0x%08x", SECTOR_2,
readBufferSector2[0], readBufferSector2[1], readBufferSector2[2],
readBufferSector2[3]);
flash_erase(flash, OFFSET_SECTOR_1, FLASH_SECTOR_SIZE);
flash_erase(flash, OFFSET_SECTOR_2, FLASH_SECTOR_SIZE);
k_sleep(K_FOREVER);
return 0;
}
prj.conf
CONFIG_LOG=y
CONFIG_FLASH=y
# It's important that Bluetooth is enabled, as only then flash_stm32wba_fm.c is used
CONFIG_BT=y
run west build -p -b nucleo_wba55cg and west flash
Expected behavior
One flash page should be erased.
Experienced behavior
Two flash pages are erased.
Logs and console output
If you disable bluetooth in prj.conf
CONFIG_BT=n
flash_stm32wba_fm.c isn't used anymore as flash driver and you can se the following output, where only one flash page is erased as expected.
Environment (please complete the following information):
- OS: Linux (Ubuntu)
- Toolchain: Zephyr SDK 0.16.8
- Zephyr OS: v3.7.0
- Board: nucleo_wba55cg